Impacts of Typhoon Bavi on Prokaryotic Communities in the Yellow Sea.

Global warming and climate change are increasingly affecting the frequency and intensity of typhoons. The vertical mixing induced by typhoons enhances the availability of nutrients, subsequently influencing phytoplankton and prokaryotic ecology. However, research on the effects of typhoons on the ecology of phytoplankton and prokaryotes in the Yellow Sea (YS) is limited. This study examined the variations in phytoplankton and prokaryotic communities in response to typhoon-induced disturbances by comparing data from the YS in August 2020 (affected by Typhoon Bavi) with data from the typhoon-free period in August 2022. Post-typhoon observations revealed a decrease in water temperature and an increase in salinity within the surface mixed layer. Significantly higher concentrations of chlorophyll-a and pigments such as peridinin, fucoxanthin, alloxanthin, and chlorophyll-b were recorded in 2020, indicating an increase in phytoplankton biomass and shifts in its composition. Although prokaryotic heterotrophic production increased at most stations following the typhoon, changes in prokaryotic abundance and composition were less evident with only minor increases observed in Verrucomicrobiales and Euryarchaeota, potentially because of insufficient time for bacterial growth to manifest in increased abundance. Overall, the changes in phytoplankton and prokaryotic communities resembled those observed during the spring bloom, suggesting that typhoons can temporarily shift the pelagic ecosystem toward a bloom state during summer. [ABSTRACT FROM AUTHOR]